Suspension Upgrade - Caterham 310S

[11Budlite]

Following on from my previous suspension post here: 

 

I've been running the stock Caterham 310S suspension on my car for the last couple years. I’m going to have access to some corner weighting scales in the near future and hope to upgrade the spring/damper combo on my Cat. Since I grew up with sports cars with leaf springs and lever shocks and since my budget is not unlimited I was looking at 1-way adjustable setups. 

 

 

I was leaning towards going with a Meteor Motorsports setup but have not contacted Simon as of yet. My car will be used almost exclusively on track at least for the time being. I'm sure Simon will have good advice concerning linear/progressive springs and weights, and linear/digressive pistons, and how to combine the two for the intended use.

 

I'm looking for any advice or experiences going from the stock Caterham Bilstein non-adjustable dampers to aftermarket. Spring weights, damper manufacture, installation issues, ease of adjustment. How often do they have to be serviced and do you have to send them back to the UK or are there companies in the US that could service them? Any advice welcome!  TIA

[Croc]

 

Do you want to set it up exclusively as a track suspension or do you want a mildly sporting upgrade from say a 310S spec to say 310R or maybe more meaty with a 310R track spec?   Trying to gauge your degree of upgrade you are aiming at.

 

A mild upgrade needn;t be spring/shocks.  You could always switch out the rubber/metalastic suspension bushings for poly bushings.  Powerflex USA in PA sell them - use the search bar to find Caterham bits as they do not list it as a maker.  Just makes everything a little crisper for track or road.  They last a hell of a lot longer than any bushing supplied by Caterham if you give them their annual attention. 

 

https://www.powerflexusa.com/shop?search=caterham

 

My suggestion would be an " R " type of upgrade with the poly bushings.  Good for track but not too extreme so you can still use it on the road when you have opportunity to plus no need to change back.

 

I find I get about 15 years out of my Caterham shocks.  There is usually a US maker who will refurb the shocks at the correct valve spec (if you know it).  For example, Meteor sell Penske shocks - you can have those serviced here.  Some will have to go back to maker in the UK - my CSR Multimatics will have to be rebuilt back there.  Bilsteins, Konis, mass market stuff sold here can be serviced here - plenty of places offer the service option.  More specialist shocks can be done by some boutique places - I have a contact in Phoenix who does it for my other cars.  You just need to know the right valving for your lightweight car.  That will be something Meteor usually keep secret but you should try to get the spec when you purchase so you can avoid having to send back in the future. 

 

[Croc]

 

Oh and to add.  I never go super firm with a Caterham as 1) I find the weight transfer helpful for maximizing grip given the lightweight nature of our cars and 2) if it is damp or raining, you want a softer suspension anyway and no one wants to be faffing around changing things from dry to wet. 

 

Its all a compromise - focusing on the sweet spot is the best answer. 

[JohnCh]

I can't comment on stock Caterham to aftermarket, but I did go with the CORE dampers and different spring rates for my recent build and can comment on dealing with Simon.  He was very helpful, talked through what I was wished to achieve, and made recommendations from there, and explained his reasoning.  I did question his spring rates -- like @Croc, Simon does not believe in stiff springs and feels the factory R offerings are over the top for road use.  However, I decided to give his rates a chance since changing springs down the road isn't a big deal.  So far, I'm very pleased.  If you haven't seen his Buyer's Guide, it's a good overview of the various options.

 

-John

[11Budlite]

Thanks for the info Croc and John. Hadn't thought of changing bushes. My plan is to use it almost exclusively for track days for now. My thought process was to be able to corner weight the car with the adjustable platforms and to be able to adjust the dampers to a softer setting in case of rain. I have read the buyers guide and was going to contact him to get his recommendations.

 

@JohnCh - I was considering the CORE dampers as well. What spring rates did he suggest for your car? I'm curious to see if there would be a different recommendation for a Duratec car as opposed to my Sigma car.   

[JohnCh]

I suspect his recommendations will be very different based on the use cases.  Given the power output of my engine, I wanted springs and dampers that could cope with high speed overtakes on our narrow, bumpy roads without risk of losing traction.  The Westfield with its 2.0L and IRS is fine, but the 2.4L and de dion was more of an unknown, and I had been advised this might be an issue.  Simon recommended digressive front dampers with linear 275 lb. springs and normal rear dampers with progressive 150 lb. springs.  Looking at my notes, he did say that for track work where consistency is important, linear springs all around are preferred.

[11Budlite]

23 minutes ago, JohnCh said:

I suspect his recommendations will be very different based on the use cases.  Given the power output of my engine, I wanted springs and dampers that could cope with high speed overtakes on our narrow, bumpy roads without risk of losing traction.  The Westfield with its 2.0L and IRS is fine, but the 2.4L and de dion was more of an unknown, and I had been advised this might be an issue.  Simon recommended digressive front dampers with linear 275 lb. springs and normal rear dampers with progressive 150 lb. springs.  Looking at my notes, he did say that for track work where consistency is important, linear springs all around are preferred.

 

Thanks John!